The aim was to understand why people practiced unprotected sex and substance abuse regarding the risk of infection by blood-borne viruses (BBVs) and sexually transmitted infections (STIs), and the factors influencing risky practices. The purpose of the study was to inform policy recommendations and improving prevention methods of BBVs/STIs among substance abusers in Egypt, particularly health/sex education in schools, media, peer groups, NGOs, and the criminal justice system.